I aquired a neat looking rock when I bought a couple of used freshwater tanks a while back. It's unusually heavy at about 10lbs, lots of porosity, and almost appears to have some iron in it. It has such a unique cave shape that I would like to add it to a 55gal salt tank which is newer and only has a a few pounds of live rock so far. There's damsels, red hermits, ceriths, established sludge, etc living in there now and happy as can be with critters growing fast. Levels are perfect. Can I just dump this rock in? I know it was previously in a fresh tank, and after I got it I washed it in the dishwasher with no soap and it's been on a coffee table since. Or would it be better to soak it in a bucket of 1.024 with powerhead or something for a few days first, or just forget it altogether because it has too much metal content or something. This thing is heavy and I dont want weird metals leaching into my SW
tank. Thanks much for your time.